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Title: Electronic structure of the kagome metal YbTi3Bi4 studied using torque magnetometry
This study investigates the electronic structure of the kagome metal YbTi3Bi4 using high-field torque magnetometry. The torque signal measured at a maximum field of 41.5 T reveals clear de Haas–van Alphen (dHvA) oscillations with a major frequency peak at Fδ ∼ 130 T. By rotating the sample at various tilt angles θ, we observed that Fδ exhibits a nearly 1/cosθ dependence, indicating the presence of a quasi-two-dimensional (2D) Fermi surface (FS) in YbTi3Bi4. This argument is further supported by the detection of a forward-leaning, sawtoothlike waveform in the dHvA effect, a hallmark of 2D FS characteristics. Notably, we identified two high-frequency peaks near Fχ ∼ 1900 T and Fλ ∼ 5600 T; however, these peaks quickly disappear at θ greater than 21◦. To better understand experimental observations, we computed the electronic band structure and FS using ab initio density-functional theory (DFT). The electronic bands reveal the presence of several Dirac points, flat bands, and van Hove singularities near the Fermi level. Five bands cross the Fermi level and contribute to the FS of this material. The FS comprises cylindrical sheets, with theoretical frequencies from the FS pockets aligning well with the experimental dHvA frequencies. Several FS parameters characterizing Fδ were determined by analyzing the temperature and field dependence of the dHvA oscillations using the Lifshitz-Kosevich theory. The detailed electronic properties presented in this work provide critical insights into the electronic structure of YbTi3Bi4 and other titanium-based kagome compounds.  more » « less
Award ID(s):
2336011
PAR ID:
10570236
Author(s) / Creator(s):
; ; ; ;
Corporate Creator(s):
Editor(s):
NA
Publisher / Repository:
American Physical Society
Date Published:
Journal Name:
Physical Review B
Volume:
111
Issue:
3
ISSN:
2469-9950
Subject(s) / Keyword(s):
Kagome torque magnetometry
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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